Source

emacs / lisp / forms.el

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
;;; forms.el --- Forms mode: edit a file as a form to fill in

;; Copyright (C) 1991, 1994, 1995, 1996 Free Software Foundation, Inc.

;; Author: Johan Vromans <jvromans@squirrel.nl>

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; Visit a file using a form.
;;
;; === Naming conventions
;;
;; The names of all variables and functions start with 'forms-'.
;; Names which start with 'forms--' are intended for internal use, and
;; should *NOT* be used from the outside.
;;
;; All variables are buffer-local, to enable multiple forms visits 
;; simultaneously.
;; Variable `forms--mode-setup' is local to *ALL* buffers, for it 
;; controls if forms-mode has been enabled in a buffer.
;;
;; === How it works ===
;;
;; Forms mode means visiting a data file which is supposed to consist
;; of records each containing a number of fields.  The records are
;; separated by a newline, the fields are separated by a user-defined
;; field separator (default: TAB).
;; When shown, a record is transferred to an Emacs buffer and
;; presented using a user-defined form.  One record is shown at a
;; time.
;;
;; Forms mode is a composite mode.  It involves two files, and two
;; buffers.
;; The first file, called the control file, defines the name of the
;; data file and the forms format.  This file buffer will be used to
;; present the forms.
;; The second file holds the actual data.  The buffer of this file
;; will be buried, for it is never accessed directly.
;;
;; Forms mode is invoked using M-x forms-find-file control-file .
;; Alternatively `forms-find-file-other-window' can be used.
;;
;; You may also visit the control file, and switch to forms mode by hand
;; with M-x forms-mode .
;;
;; Automatic mode switching is supported if you specify 
;; "-*- forms -*-" in the first line of the control file.
;; 
;; The control file is visited, evaluated using `eval-current-buffer',
;; and should set at least the following variables:
;;
;;	forms-file				[string]
;;			The name of the data file.
;;
;;	forms-number-of-fields			[integer]
;;			The number of fields in each record.
;;
;;	forms-format-list			[list]
;;			Formatting instructions.
;;
;; `forms-format-list' should be a list, each element containing
;;
;;   - a string, e.g. "hello".  The string is inserted in the forms
;;	"as is".
;;   
;;   - an integer, denoting a field number.
;;	The contents of this field are inserted at this point.
;;     Fields are numbered starting with number one.
;;   
;;   - a function call, e.g. (insert "text").
;;	This function call is dynamically evaluated and should return a
;;     string.  It should *NOT* have side-effects on the forms being
;;     constructed.  The current fields are available to the function
;;     in the variable `forms-fields', they should *NOT* be modified.
;;   
;;   - a lisp symbol, that must evaluate to one of the above.
;;
;; Optional variables which may be set in the control file:
;;
;;	forms-field-sep				[string, default TAB]
;;			The field separator used to separate the
;;			fields in the data file.  It may be a string.
;;
;;	forms-read-only				[bool, default nil]
;;			Non-nil means that the data file is visited
;;			read-only (view mode) as opposed to edit mode.
;;			If no write access to the data file is
;;			possible, view mode is enforced. 
;;
;;	forms-check-number-of-fields            [bool, default t]
;;			If non-nil, a warning will be issued whenever
;;			a record is found that does not have the number
;;			of fields specified by `forms-number-of-fields'.
;;
;;	forms-multi-line			[string, default "^K"]
;;			If non-null the records of the data file may
;;			contain fields that can span multiple lines in
;;			the form.
;;			This variable denotes the separator character
;;			to be used for this purpose.  Upon display, all
;;			occurrences of this character are translated
;;			to newlines.  Upon storage they are translated
;;			back to the separator character.
;;
;;	forms-forms-scroll			[bool, default nil]
;;			Non-nil means: rebind locally the commands that
;;			perform `scroll-up' or `scroll-down' to use
;;			`forms-next-field' resp. `forms-prev-field'.
;;
;;	forms-forms-jump			[bool, default nil]
;;			Non-nil means: rebind locally the commands that
;;
;;	forms-insert-after			[bool, default nil]
;;			Non-nil means: inserts of new records go after
;;			current record, also initial position is at last
;;			record.
;;
;;	forms-read-file-filter			[symbol, default nil]
;;			If not nil: this should be the name of a 
;;			function that is called after the forms data file
;;			has been read.  It can be used to transform
;;			the contents of the file into a format more suitable
;;			for forms-mode processing.
;;
;;	forms-write-file-filter			[symbol, default nil]
;;			If not nil: this should be the name of a 
;;			function that is called before the forms data file
;;			is written (saved) to disk.  It can be used to undo
;;			the effects of `forms-read-file-filter', if any.
;;
;;	forms-new-record-filter			[symbol, default nil]
;;			If not nil: this should be the name of a 
;;			function that is called when a new
;;			record is created.  It can be used to fill in
;;			the new record with default fields, for example.
;;
;;	forms-modified-record-filter		[symbol, default nil]
;;			If not nil: this should be the name of a 
;;			function that is called when a record has
;;			been modified.  It is called after the fields
;;			are parsed.  It can be used to register
;;			modification dates, for example.
;;
;;	forms-use-text-properties		[bool, see text for default]
;;			This variable controls if forms mode should use
;;			text properties to protect the form text from being
;;			modified (using text-property `read-only').
;;			Also, the read-write fields are shown using a
;;			distinct face, if possible.
;;			As of emacs 19.29, the `intangible' text property
;;			is used to prevent moving into read-only fields.
;;			This variable defaults to t if running Emacs 19
;;			with text properties.
;;			The default face to show read-write fields is
;;			copied from face `region'.
;;
;;	forms-ro-face 				[symbol, default 'default]
;;			This is the face that is used to show
;;			read-only text on the screen.If used, this
;;			variable should be set to a symbol that is a
;;			valid face.
;;			E.g.
;;			  (make-face 'my-face)
;;			  (setq forms-ro-face 'my-face)
;;
;;	forms-rw-face				[symbol, default 'region]
;;			This is the face that is used to show
;;			read-write text on the screen.
;;
;; After evaluating the control file, its buffer is cleared and used
;; for further processing.
;; The data file (as designated by `forms-file') is visited in a buffer
;; `forms--file-buffer' which will not normally be shown.
;; Great malfunctioning may be expected if this file/buffer is modified
;; outside of this package while it is being visited!
;;
;; Normal operation is to transfer one line (record) from the data file,
;; split it into fields (into `forms--the-record-list'), and display it
;; using the specs in `forms-format-list'.
;; A format routine `forms--format' is built upon startup to format 
;; the records according to `forms-format-list'.
;;
;; When a form is changed the record is updated as soon as this form
;; is left.  The contents of the form are parsed using information
;; obtained from `forms-format-list', and the fields which are
;; deduced from the form are modified.  Fields not shown on the forms
;; retain their original values.  The newly formed record then
;; replaces the contents of the old record in `forms--file-buffer'.
;; A parse routine `forms--parser' is built upon startup to parse
;; the records.
;;
;; Two exit functions exist: `forms-exit' and `forms-exit-no-save'.
;; `forms-exit' saves the data to the file, if modified.
;; `forms-exit-no-save` does not.  However, if `forms-exit-no-save'
;; is executed and the file buffer has been modified, Emacs will ask
;; questions anyway.
;;
;; Other functions provided by forms mode are:
;;
;;	paging (forward, backward) by record
;;	jumping (first, last, random number)
;;	searching
;;	creating and deleting records
;;	reverting the form (NOT the file buffer)
;;	switching edit <-> view mode v.v.
;;	jumping from field to field
;;
;; As an documented side-effect: jumping to the last record in the
;; file (using forms-last-record) will adjust forms--total-records if
;; needed.
;;
;; The forms buffer can be in on eof two modes: edit mode or view
;; mode.  View mode is a read-only mode, you cannot modify the
;; contents of the buffer.
;;
;; Edit mode commands:
;; 
;; TAB		 forms-next-field
;; \C-c TAB	 forms-next-field
;; \C-c <	 forms-first-record
;; \C-c >	 forms-last-record
;; \C-c ?	 describe-mode
;; \C-c \C-k	 forms-delete-record
;; \C-c \C-q	 forms-toggle-read-only
;; \C-c \C-o	 forms-insert-record
;; \C-c \C-l	 forms-jump-record
;; \C-c \C-n	 forms-next-record
;; \C-c \C-p	 forms-prev-record
;; \C-c \C-r	 forms-search-backward
;; \C-c \C-s	 forms-search-forward
;; \C-c \C-x	 forms-exit
;; 
;; Read-only mode commands:
;; 
;; SPC 	 forms-next-record
;; DEL	 forms-prev-record
;; ?	 describe-mode
;; \C-q forms-toggle-read-only
;; l	 forms-jump-record
;; n	 forms-next-record
;; p	 forms-prev-record
;; r	 forms-search-backward
;; s	 forms-search-forward
;; x	 forms-exit
;; 
;; Of course, it is also possible to use the \C-c prefix to obtain the
;; same command keys as in edit mode.
;; 
;; The following bindings are available, independent of the mode: 
;; 
;; [next]	  forms-next-record
;; [prior]	  forms-prev-record
;; [begin]	  forms-first-record
;; [end]	  forms-last-record
;; [S-TAB]	  forms-prev-field
;; [backtab] forms-prev-field
;;
;; For convenience, TAB is always bound to `forms-next-field', so you
;; don't need the C-c prefix for this command.
;;
;; As mentioned above (see `forms-forms-scroll' and `forms-forms-jump')
;; the bindings of standard functions `scroll-up', `scroll-down',
;; `beginning-of-buffer' and `end-of-buffer' can be locally replaced with
;; forms mode functions next/prev record and first/last
;; record.
;;
;; `local-write-file hook' is defined to save the actual data file
;; instead of the buffer data, `revert-file-hook' is defined to
;; revert a forms to original.

;;; Code:

;;; Global variables and constants:

(provide 'forms)			;;; official
(provide 'forms-mode)			;;; for compatibility

(defconst forms-version (substring "$Revision: 2.20 $" 11 -2)
  "The version number of forms-mode (as string).  The complete RCS id is:

  $Id: forms.el,v 2.20 1996/03/01 20:31:29 jv Exp $")

(defvar forms-mode-hooks nil
  "Hook functions to be run upon entering Forms mode.")

;;; Mandatory variables - must be set by evaluating the control file.

(defvar forms-file nil
  "Name of the file holding the data.")

(defvar forms-format-list nil
  "List of formatting specifications.")

(defvar forms-number-of-fields nil
  "Number of fields per record.")

;;; Optional variables with default values.

(defvar forms-check-number-of-fields t
  "*If non-nil, warn about records with wrong number of fields.")

(defvar forms-field-sep "\t"
  "Field separator character (default TAB).")

(defvar forms-read-only nil
  "Non-nil means: visit the file in view (read-only) mode.
\(Defaults to the write access on the data file).")

(defvar forms-multi-line "\C-k"
  "If not nil: use this character to separate multi-line fields (default C-k).")

(defvar forms-forms-scroll nil
  "*Non-nil means replace scroll-up/down commands in Forms mode.
The replacement commands performs forms-next/prev-record.")

(defvar forms-forms-jump nil
  "*Non-nil means redefine beginning/end-of-buffer in Forms mode.
The replacement commands performs forms-first/last-record.")

(defvar forms-read-file-filter nil
  "The name of a function that is called after reading the data file.
This can be used to change the contents of the file to something more
suitable for forms processing.")

(defvar forms-write-file-filter nil
  "The name of a function that is called before writing the data file.
This can be used to undo the effects of form-read-file-hook.")

(defvar forms-new-record-filter nil
  "The name of a function that is called when a new record is created.")

(defvar forms-modified-record-filter nil
  "The name of a function that is called when a record has been modified.")

(defvar forms-fields nil
  "List with fields of the current forms.  First field has number 1.
This variable is for use by the filter routines only. 
The contents may NOT be modified.")

(defvar forms-use-text-properties (fboundp 'set-text-properties)
  "*Non-nil means: use emacs-19 text properties.
Defaults to t if this emacs is capable of handling text properties.")

(defvar forms-insert-after nil
  "*Non-nil means: inserts of new records go after current record.
Also, initial position is at last record.")

(defvar forms-ro-face 'default
  "The face (a symbol) that is used to display read-only text on the screen.")

(defvar forms-rw-face 'region
  "The face (a symbol) that is used to display read-write text on the screen.")

;;; Internal variables.

(defvar forms--file-buffer nil
  "Buffer which holds the file data")

(defvar forms--total-records 0
  "Total number of records in the data file.")

(defvar forms--current-record 0
  "Number of the record currently on the screen.")

(defvar forms-mode-map nil
   "Keymap for form buffer.")
(defvar forms-mode-ro-map nil
   "Keymap for form buffer in view mode.")
(defvar forms-mode-edit-map nil
   "Keymap for form buffer in edit mode.")

(defvar forms--markers nil
  "Field markers in the screen.")

(defvar forms--dyntexts nil
  "Dynamic texts (resulting from function calls) on the screen.")

(defvar forms--the-record-list nil 
   "List of strings of the current record, as parsed from the file.")

(defvar forms--search-regexp nil
  "Last regexp used by forms-search functions.")

(defvar forms--format nil
  "Formatting routine.")

(defvar forms--parser nil
  "Forms parser routine.")

(defvar forms--mode-setup nil
  "To keep track of forms-mode being set-up.")
(make-variable-buffer-local 'forms--mode-setup)

(defvar forms--dynamic-text nil
  "Array that holds dynamic texts to insert between fields.")

(defvar forms--elements nil
  "Array with the order in which the fields are displayed.")

(defvar forms--ro-face nil
  "Face used to represent read-only data on the screen.")

(defvar forms--rw-face nil
  "Face used to represent read-write data on the screen.")

;;;###autoload 
(defun forms-mode (&optional primary)
  "Major mode to visit files in a field-structured manner using a form.

Commands:                        Equivalent keys in read-only mode:
 TAB            forms-next-field          TAB
 \\C-c TAB       forms-next-field          
 \\C-c <         forms-first-record         <
 \\C-c >         forms-last-record          >
 \\C-c ?         describe-mode              ?
 \\C-c \\C-k      forms-delete-record
 \\C-c \\C-q      forms-toggle-read-only     q
 \\C-c \\C-o      forms-insert-record
 \\C-c \\C-l      forms-jump-record          l
 \\C-c \\C-n      forms-next-record          n
 \\C-c \\C-p      forms-prev-record          p
 \\C-c \\C-r      forms-search-reverse       r
 \\C-c \\C-s      forms-search-forward       s
 \\C-c \\C-x      forms-exit                 x
"
  (interactive)

  ;; This is not a simple major mode, as usual.  Therefore, forms-mode
  ;; takes an optional argument `primary' which is used for the
  ;; initial set-up.  Normal use would leave `primary' to nil.
  ;; A global buffer-local variable `forms--mode-setup' has the same
  ;; effect but makes it possible to auto-invoke forms-mode using
  ;; `find-file'.
  ;; Note: although it seems logical to have `make-local-variable'
  ;; executed where the variable is first needed, I have deliberately
  ;; placed all calls in this function.

  ;; Primary set-up: evaluate buffer and check if the mandatory
  ;; variables have been set.
  (if (or primary (not forms--mode-setup))
      (progn
	;;(message "forms: setting up...")
	(kill-all-local-variables)

	;; Make mandatory variables.
	(make-local-variable 'forms-file)
	(make-local-variable 'forms-number-of-fields)
	(make-local-variable 'forms-format-list)

	;; Make optional variables.
	(make-local-variable 'forms-field-sep)
        (make-local-variable 'forms-read-only)
        (make-local-variable 'forms-multi-line)
	(make-local-variable 'forms-forms-scroll)
	(make-local-variable 'forms-forms-jump)
	(make-local-variable 'forms-insert-after)
	(make-local-variable 'forms-use-text-properties)

	;; Filter functions.
	(make-local-variable 'forms-read-file-filter)
	(make-local-variable 'forms-write-file-filter)
	(make-local-variable 'forms-new-record-filter)
	(make-local-variable 'forms-modified-record-filter)

	;; Make sure no filters exist.
	(setq forms-read-file-filter nil)
	(setq forms-write-file-filter nil)
	(setq forms-new-record-filter nil)
	(setq forms-modified-record-filter nil)

	;; If running Emacs 19 under X, setup faces to show read-only and 
	;; read-write fields.
	(if (fboundp 'make-face)
	    (progn
	      (make-local-variable 'forms-ro-face)
	      (make-local-variable 'forms-rw-face)))

	;; eval the buffer, should set variables
	;;(message "forms: processing control file...")
	;; If enable-local-eval is not set to t the user is asked first.
	(if (or (eq enable-local-eval t)
		(yes-or-no-p 
		 (concat "Evaluate lisp code in buffer "
			 (buffer-name) " to display forms ")))
	    (eval-current-buffer)
	  (error "`enable-local-eval' inhibits buffer evaluation"))

	;; Check if the mandatory variables make sense.
	(or forms-file
	    (error (concat "Forms control file error: " 
			   "'forms-file' has not been set")))

	;; Check forms-field-sep first, since it can be needed to
	;; construct a default format list.
	(or (stringp forms-field-sep)
	    (error (concat "Forms control file error: "
			   "'forms-field-sep' is not a string")))

	(if forms-number-of-fields
	    (or (and (numberp forms-number-of-fields)
		     (> forms-number-of-fields 0))
		(error (concat "Forms control file error: "
			       "'forms-number-of-fields' must be a number > 0")))
	  (or (null forms-format-list)
	      (error (concat "Forms control file error: "
			     "'forms-number-of-fields' has not been set"))))

	(or forms-format-list
	    (forms--intuit-from-file))

	(if forms-multi-line
	    (if (and (stringp forms-multi-line)
		     (eq (length forms-multi-line) 1))
		(if (string= forms-multi-line forms-field-sep)
		    (error (concat "Forms control file error: " 
				   "'forms-multi-line' is equal to 'forms-field-sep'")))
	      (error (concat "Forms control file error: "
			     "'forms-multi-line' must be nil or a one-character string"))))
	(or (fboundp 'set-text-properties)
	    (setq forms-use-text-properties nil))
	    
	;; Validate and process forms-format-list.
	;;(message "forms: pre-processing format list...")
	(forms--process-format-list)

	;; Build the formatter and parser.
	;;(message "forms: building formatter...")
	(make-local-variable 'forms--format)
	(make-local-variable 'forms--markers)
	(make-local-variable 'forms--dyntexts)
	(make-local-variable 'forms--elements)
	;;(message "forms: building parser...")
	(forms--make-format)
	(make-local-variable 'forms--parser)
	(forms--make-parser)
	;;(message "forms: building parser... done.")

	;; Check if record filters are defined.
	(if (and forms-new-record-filter
		 (not (fboundp forms-new-record-filter)))
	    (error (concat "Forms control file error: "
			   "'forms-new-record-filter' is not a function")))

	(if (and forms-modified-record-filter
		 (not (fboundp forms-modified-record-filter)))
	    (error (concat "Forms control file error: "
			   "'forms-modified-record-filter' is not a function")))

	;; The filters acces the contents of the forms using `forms-fields'.
	(make-local-variable 'forms-fields)

	;; Dynamic text support.
	(make-local-variable 'forms--dynamic-text)

	;; Prevent accidental overwrite of the control file and autosave.
	(set-visited-file-name nil)

	;; Prepare this buffer for further processing.
	(setq buffer-read-only nil)
	(erase-buffer)

	;;(message "forms: setting up... done.")
	))

  ;; initialization done
  (setq forms--mode-setup t)

  ;; Copy desired faces to the actual variables used by the forms formatter.
  (if (fboundp 'make-face)
      (progn
	(make-local-variable 'forms--ro-face)
	(make-local-variable 'forms--rw-face)
	(if forms-read-only
	    (progn
	      (setq forms--ro-face forms-ro-face)
	      (setq forms--rw-face forms-ro-face))
	  (setq forms--ro-face forms-ro-face)
	  (setq forms--rw-face forms-rw-face))))

  ;; Make more local variables.
  (make-local-variable 'forms--file-buffer)
  (make-local-variable 'forms--total-records)
  (make-local-variable 'forms--current-record)
  (make-local-variable 'forms--the-record-list)
  (make-local-variable 'forms--search-regexp)

  ; The keymaps are global, so multiple forms mode buffers can share them.
  ;(make-local-variable 'forms-mode-map)
  ;(make-local-variable 'forms-mode-ro-map)
  ;(make-local-variable 'forms-mode-edit-map)
  (if forms-mode-map			; already defined
      nil
    ;;(message "forms: building keymap...")
    (forms--mode-commands)
    ;;(message "forms: building keymap... done.")
    )

  ;; set the major mode indicator
  (setq major-mode 'forms-mode)
  (setq mode-name "Forms")

  ;; find the data file
  (setq forms--file-buffer (find-file-noselect forms-file))

  ;; Pre-transform.
  (let ((read-file-filter forms-read-file-filter)
	(write-file-filter forms-write-file-filter))
    (if read-file-filter
	(save-excursion
	  (set-buffer forms--file-buffer)
	  (let ((inhibit-read-only t)
		(file-modified (buffer-modified-p)))
	    (run-hooks 'read-file-filter)
	    (if (not file-modified) (set-buffer-modified-p nil)))
	  (if write-file-filter
	      (progn
		(make-variable-buffer-local 'local-write-file-hooks)
		(setq local-write-file-hooks (list write-file-filter)))))
      (if write-file-filter
	  (save-excursion
	    (set-buffer forms--file-buffer)
	    (make-variable-buffer-local 'local-write-file-hooks)
	    (setq local-write-file-hooks (list write-file-filter))))))

  ;; count the number of records, and set see if it may be modified
  (let (ro)
    (setq forms--total-records
	  (save-excursion
	    (prog1
		(progn
		  ;;(message "forms: counting records...")
		  (set-buffer forms--file-buffer)
		  (bury-buffer (current-buffer))
		  (setq ro buffer-read-only)
		  (count-lines (point-min) (point-max)))
	      ;;(message "forms: counting records... done.")
	      )))
    (if ro
	(setq forms-read-only t)))

  ;;(message "forms: proceeding setup...")

  ;; Since we aren't really implementing a minor mode, we hack the modeline
  ;; directly to get the text " View " into forms-read-only form buffers.  For
  ;; that reason, this variable must be buffer only.
  (make-local-variable 'minor-mode-alist)
  (setq minor-mode-alist (list (list 'forms-read-only " View")))

  ;;(message "forms: proceeding setup (keymaps)...")
  (forms--set-keymaps)
  ;;(message "forms: proceeding setup (commands)...")
  (forms--change-commands)

  ;;(message "forms: proceeding setup (buffer)...")
  (set-buffer-modified-p nil)

  (if (= forms--total-records 0)
      ;;(message "forms: proceeding setup (new file)...")
      (progn
	(insert 
	 "GNU Emacs Forms Mode version " forms-version "\n\n"
	 (if (file-exists-p forms-file)
	     (concat "No records available in file `" forms-file "'\n\n")
	   (format "Creating new file `%s'\nwith %d field%s per record\n\n"
		   forms-file forms-number-of-fields
		   (if (= 1 forms-number-of-fields) "" "s")))
	 "Use " (substitute-command-keys "\\[forms-insert-record]")
	 " to create new records.\n")
	(setq forms--current-record 1)
	(setq buffer-read-only t)
	(set-buffer-modified-p nil))

    ;; setup the first (or current) record to show
    (if (< forms--current-record 1)
	(setq forms--current-record 1))
    (forms-jump-record forms--current-record)
    )

  (if forms-insert-after
      (forms-last-record)
    (forms-first-record))

  ;; user customising
  ;;(message "forms: proceeding setup (user hooks)...")
  (run-hooks 'forms-mode-hooks)
  ;;(message "forms: setting up... done.")

  ;; be helpful
  (forms--help)
)

(defun forms--process-format-list ()
  ;; Validate `forms-format-list' and set some global variables.
  ;; Symbols in the list are evaluated, and consecutive strings are
  ;; concatenated.
  ;; Array `forms--elements' is constructed that contains the order
  ;; of the fields on the display. This array is used by 
  ;; `forms--parser-using-text-properties' to extract the fields data
  ;; from the form on the screen.
  ;; Upon completion, `forms-format-list' is guaranteed correct, so
  ;; `forms--make-format' and `forms--make-parser' do not need to perform
  ;; any checks.

  ;; Verify that `forms-format-list' is not nil.
  (or forms-format-list
      (error (concat "Forms control file error: "
		     "'forms-format-list' has not been set")))
  ;; It must be a list.
  (or (listp forms-format-list)
      (error (concat "Forms control file error: "
		     "'forms-format-list' is not a list")))

  ;; Assume every field is painted once.
  ;; `forms--elements' will grow if needed.
  (setq forms--elements (make-vector forms-number-of-fields nil))

  (let ((the-list forms-format-list)	; the list of format elements
	(this-item 0)			; element in list
	(prev-item nil)
	(field-num 0))			; highest field number 

    (setq forms-format-list nil)	; gonna rebuild

    (while the-list

      (let ((el (car-safe the-list))
	    (rem (cdr-safe the-list)))

	;; If it is a symbol, eval it first.
	(if (and (symbolp el)
		 (boundp el))
	    (setq el (eval el)))

	(cond

	 ;; Try string ...
	 ((stringp el)
	  (if (stringp prev-item)	; try to concatenate strings
	      (setq prev-item (concat prev-item el))
	    (if prev-item
		(setq forms-format-list
		      (append forms-format-list (list prev-item) nil)))
	    (setq prev-item el)))

	 ;; Try numeric ...
	 ((numberp el) 

	  ;; Validate range.
	  (if (or (<= el 0)
		  (> el forms-number-of-fields))
	      (error (concat "Forms format error: "
			     "field number %d out of range 1..%d")
		     el forms-number-of-fields))

	  ;; Store forms order.
	  (if (> field-num (length forms--elements))
	      (setq forms--elements (vconcat forms--elements (1- el)))
	    (aset forms--elements field-num (1- el)))
	  (setq field-num (1+ field-num))

	  (if prev-item
	      (setq forms-format-list
		    (append forms-format-list (list prev-item) nil)))
	  (setq prev-item el))

	 ;; Try function ...
	 ((listp el)

	  ;; Validate.
	  (or (fboundp (car-safe el))
	      (error (concat "Forms format error: "
			     "not a function %S")
		     (car-safe el)))

	  ;; Shift.
	  (if prev-item
	      (setq forms-format-list
		    (append forms-format-list (list prev-item) nil)))
	  (setq prev-item el))

	 ;; else
	 (t
	  (error (concat "Forms format error: "
			 "invalid element %S")
		 el)))

	;; Advance to next element of the list.
	(setq the-list rem)))

    ;; Append last item.
    (if prev-item
	(progn
	  (setq forms-format-list
		(append forms-format-list (list prev-item) nil))
	  ;; Append a newline if the last item is a field.
	  ;; This prevents parsing problems.
	  ;; Also it makes it possible to insert an empty last field.
	  (if (numberp prev-item)
	      (setq forms-format-list
		    (append forms-format-list (list "\n") nil))))))

  (forms--debug 'forms-format-list
		'forms--elements))

;; Special treatment for read-only segments.
;;
;; If text is inserted between two read-only segments, it inherits the
;; read-only properties.  This is not what we want.
;; To solve this, read-only segments get the `insert-in-front-hooks'
;; property set with a function that temporarily switches the properties
;; of the first character of the segment to read-write, so the new
;; text gets the right properties.
;; The `post-command-hook' is used to restore the original properties.

(defvar forms--iif-start nil
  "Record start of modification command.")
(defvar forms--iif-properties nil
  "Original properties of the character being overridden.")

(defun forms--iif-hook (begin end)
  "`insert-in-front-hooks' function for read-only segments."

  ;; Note start location.  By making it a marker that points one 
  ;; character beyond the actual location, it is guaranteed to move 
  ;; correctly if text is inserted.
  (or forms--iif-start
      (setq forms--iif-start (copy-marker (1+ (point)))))

  ;; Check if there is special treatment required.
  (if (or (<= forms--iif-start 2)
	  (get-text-property (- forms--iif-start 2)
			     'read-only))
      (progn
	;; Fetch current properties.
	(setq forms--iif-properties 
	      (text-properties-at (1- forms--iif-start)))

	;; Replace them.
	(let ((inhibit-read-only t))
	  (set-text-properties 
	   (1- forms--iif-start) forms--iif-start
	   (list 'face forms--rw-face 'front-sticky '(face))))

	;; Enable `post-command-hook' to restore the properties.
	(setq post-command-hook
	      (append (list 'forms--iif-post-command-hook) post-command-hook)))

    ;; No action needed.  Clear marker.
    (setq forms--iif-start nil)))

(defun forms--iif-post-command-hook ()
  "`post-command-hook' function for read-only segments."

  ;; Disable `post-command-hook'.
  (setq post-command-hook
	(delq 'forms--iif-hook-post-command-hook post-command-hook))

  ;; Restore properties.
  (if forms--iif-start
      (let ((inhibit-read-only t))
	(set-text-properties 
	 (1- forms--iif-start) forms--iif-start
	 forms--iif-properties)))

  ;; Cleanup.
  (setq forms--iif-start nil))

(defvar forms--marker)
(defvar forms--dyntext)

(defun forms--make-format ()
  "Generate `forms--format' using the information in `forms-format-list'."

  ;; The real work is done using a mapcar of `forms--make-format-elt' on
  ;; `forms-format-list'.
  ;; This function sets up the necessary environment, and decides
  ;; which function to mapcar.

  (let ((forms--marker 0)
	(forms--dyntext 0))
    (setq 
     forms--format
     (if forms-use-text-properties 
	 (` (lambda (arg)
	      (let ((inhibit-read-only t))
		(,@ (apply 'append
			   (mapcar 'forms--make-format-elt-using-text-properties
				   forms-format-list)))
		;; Prevent insertion before the first text.
		(,@ (if (numberp (car forms-format-list))
			nil
		      '((add-text-properties (point-min) (1+ (point-min))
					     '(front-sticky (read-only intangible))))))
		;; Prevent insertion after the last text.
		(remove-text-properties (1- (point)) (point)
					'(rear-nonsticky)))
	      (setq forms--iif-start nil)))
       (` (lambda (arg)
	    (,@ (apply 'append
		       (mapcar 'forms--make-format-elt forms-format-list)))))))

    ;; We have tallied the number of markers and dynamic texts,
    ;; so we can allocate the arrays now.
    (setq forms--markers (make-vector forms--marker nil))
    (setq forms--dyntexts (make-vector forms--dyntext nil)))
  (forms--debug 'forms--format))

(defun forms--make-format-elt-using-text-properties (el)
  "Helper routine to generate format function."

  ;; The format routine `forms--format' will look like
  ;;
  ;; ;; preamble
  ;; (lambda (arg)
  ;;   (let ((inhibit-read-only t))
  ;;
  ;;     ;; A string, e.g. "text: ".
  ;;     (set-text-properties 
  ;;      (point)
  ;;      (progn (insert "text: ") (point)) 
  ;;      (list 'face forms--ro-face
  ;;		'read-only 1
  ;;		'insert-in-front-hooks 'forms--iif-hook
  ;;		'rear-nonsticky '(read-only face insert-in-front-hooks)))
  ;;
  ;;     ;; A field, e.g. 6.
  ;;     (let ((here (point)))
  ;;       (aset forms--markers 0 (point-marker))
  ;;       (insert (elt arg 5))
  ;;       (or (= (point) here)
  ;; 	  (set-text-properties 
  ;; 	   here (point)
  ;; 	   (list 'face forms--rw-face
  ;;		 'front-sticky '(face))))
  ;;
  ;;     ;; Another string, e.g. "\nmore text: ".
  ;;     (set-text-properties
  ;;      (point)
  ;;      (progn (insert "\nmore text: ") (point))
  ;;      (list 'face forms--ro-face
  ;;		'read-only 2
  ;;		'insert-in-front-hooks 'forms--iif-hook
  ;;		'rear-nonsticky '(read-only face insert-in-front-hooks)))
  ;;
  ;;     ;; A function, e.g. (tocol 40).
  ;;     (set-text-properties
  ;;      (point)
  ;;      (progn
  ;;        (insert (aset forms--dyntexts 0 (tocol 40)))
  ;;        (point))
  ;;      (list 'face forms--ro-face
  ;;		'read-only 2
  ;;		'insert-in-front-hooks 'forms--iif-hook
  ;;		'rear-nonsticky '(read-only face insert-in-front-hooks)))
  ;;
  ;;	 ;; Prevent insertion before the first text.
  ;;	 (add-text-properties (point-min) (1+ (point-min))
  ;;			      '(front-sticky (read-only))))))
  ;;	 ;; Prevent insertion after the last text.
  ;;	 (remove-text-properties (1- (point)) (point)
  ;;	 			 '(rear-nonsticky)))
  ;;
  ;;     ;; wrap up
  ;;     (setq forms--iif-start nil)
  ;;     ))

  (cond
   ((stringp el)
    
    (` ((set-text-properties 
	 (point)			; start at point
	 (progn				; until after insertion
	   (insert (, el))
	   (point))
	 (list 'face forms--ro-face	; read-only appearance
	       'read-only (,@ (list (1+ forms--marker)))
	       'intangible t
	       'insert-in-front-hooks '(forms--iif-hook)
	       'rear-nonsticky '(face read-only insert-in-front-hooks
				 intangible))))))
    
   ((numberp el)
    (` ((let ((here (point)))
	  (aset forms--markers 
		(, (prog1 forms--marker
		     (setq forms--marker (1+ forms--marker))))
		(point-marker))
	  (insert (elt arg (, (1- el))))
	  (or (= (point) here)
	      (set-text-properties 
	       here (point)
	       (list 'face forms--rw-face
		     'front-sticky '(face))))))))

   ((listp el)
    (` ((set-text-properties
	 (point)
	 (progn
	   (insert (aset forms--dyntexts 
			 (, (prog1 forms--dyntext
			      (setq forms--dyntext (1+ forms--dyntext))))
			 (, el)))
	   (point))
	 (list 'face forms--ro-face
	       'read-only (,@ (list (1+ forms--marker)))
	       'intangible t
	       'insert-in-front-hooks '(forms--iif-hook)
	       'rear-nonsticky '(read-only face insert-in-front-hooks
				 intangible))))))

   ;; end of cond
   ))

(defun forms--make-format-elt (el)
  "Helper routine to generate format function."

  ;; If we're not using text properties, the format routine
  ;; `forms--format' will look like
  ;;
  ;; (lambda (arg)
  ;;   ;; a string, e.g. "text: "
  ;;   (insert "text: ")
  ;;   ;; a field, e.g. 6
  ;;   (aset forms--markers 0 (point-marker))
  ;;   (insert (elt arg 5))
  ;;   ;; another string, e.g. "\nmore text: "
  ;;   (insert "\nmore text: ")
  ;;   ;; a function, e.g. (tocol 40)
  ;;   (insert (aset forms--dyntexts 0 (tocol 40)))
  ;;   ... )

  (cond 
   ((stringp el)
    (` ((insert (, el)))))
   ((numberp el)
    (prog1
	(` ((aset forms--markers (, forms--marker) (point-marker))
	    (insert (elt arg (, (1- el))))))
      (setq forms--marker (1+ forms--marker))))
   ((listp el)
    (prog1
	(` ((insert (aset forms--dyntexts (, forms--dyntext) (, el)))))
      (setq forms--dyntext (1+ forms--dyntext))))))

(defvar forms--field)
(defvar forms--recordv)
(defvar forms--seen-text)

(defun forms--make-parser ()
  "Generate `forms--parser' from the information in `forms-format-list'."

  ;; If we can use text properties, we simply set it to
  ;; `forms--parser-using-text-properties'.
  ;; Otherwise, the function is constructed using a mapcar of
  ;; `forms--make-parser-elt on `forms-format-list'.

  (setq
   forms--parser
   (if forms-use-text-properties
       (function forms--parser-using-text-properties)
     (let ((forms--field nil)
	   (forms--seen-text nil)
	   (forms--dyntext 0))

       ;; Note: we add a nil element to the list passed to `mapcar',
       ;; see `forms--make-parser-elt' for details.
       (` (lambda nil
	    (let (here)
	      (goto-char (point-min))
	      (,@ (apply 'append
			 (mapcar 
			  'forms--make-parser-elt 
			  (append forms-format-list (list nil)))))))))))

  (forms--debug 'forms--parser))

(defun forms--parser-using-text-properties ()
  "Extract field info from forms when using text properties."

  ;; Using text properties, we can simply jump to the markers, and
  ;; extract the information up to the following read-only segment.

  (let ((i 0)
	here there)
    (while (< i (length forms--markers))
      (goto-char (setq here (aref forms--markers i)))
      (if (get-text-property here 'read-only)
	  (aset forms--recordv (aref forms--elements i) nil)
	(if (setq there 
		  (next-single-property-change here 'read-only))
	    (aset forms--recordv (aref forms--elements i)
		  (buffer-substring-no-properties here there))
	  (aset forms--recordv (aref forms--elements i)
		(buffer-substring-no-properties here (point-max)))))
      (setq i (1+ i)))))

(defun forms--make-parser-elt (el)
  "Helper routine to generate forms parser function."

  ;; The parse routine will look like:
  ;;
  ;; (lambda nil
  ;;   (let (here)
  ;;     (goto-char (point-min))
  ;; 
  ;;	 ;;  "text: "
  ;;     (if (not (looking-at "text: "))
  ;; 	    (error "Parse error: cannot find \"text: \""))
  ;;     (forward-char 6)	; past "text: "
  ;; 
  ;;     ;;  6
  ;;	 ;;  "\nmore text: "
  ;;     (setq here (point))
  ;;     (if (not (search-forward "\nmore text: " nil t nil))
  ;; 	    (error "Parse error: cannot find \"\\nmore text: \""))
  ;;     (aset forms--recordv 5 (buffer-substring-no-properties here (- (point) 12)))
  ;;
  ;;	 ;;  (tocol 40)
  ;;	(let ((forms--dyntext (car-safe forms--dynamic-text)))
  ;;	  (if (not (looking-at (regexp-quote forms--dyntext)))
  ;;	      (error "Parse error: not looking at \"%s\"" forms--dyntext))
  ;;	  (forward-char (length forms--dyntext))
  ;;	  (setq forms--dynamic-text (cdr-safe forms--dynamic-text)))
  ;;     ... 
  ;;     ;; final flush (due to terminator sentinel, see below)
  ;;	(aset forms--recordv 7 (buffer-substring-no-properties (point) (point-max)))

  (cond
   ((stringp el)
    (prog1
	(if forms--field
	    (` ((setq here (point))
		(if (not (search-forward (, el) nil t nil))
		    (error "Parse error: cannot find \"%s\"" (, el)))
		(aset forms--recordv (, (1- forms--field))
		      (buffer-substring-no-properties here
					(- (point) (, (length el)))))))
	  (` ((if (not (looking-at (, (regexp-quote el))))
		  (error "Parse error: not looking at \"%s\"" (, el)))
	      (forward-char (, (length el))))))
      (setq forms--seen-text t)
      (setq forms--field nil)))
   ((numberp el)
    (if forms--field
	(error "Cannot parse adjacent fields %d and %d"
	       forms--field el)
      (setq forms--field el)
      nil))
   ((null el)
    (if forms--field
	(` ((aset forms--recordv (, (1- forms--field))
		  (buffer-substring-no-properties (point) (point-max)))))))
   ((listp el)
    (prog1
	(if forms--field
	    (` ((let ((here (point))
		      (forms--dyntext (aref forms--dyntexts (, forms--dyntext))))
		  (if (not (search-forward forms--dyntext nil t nil))
		      (error "Parse error: cannot find \"%s\"" forms--dyntext))
		  (aset forms--recordv (, (1- forms--field))
			(buffer-substring-no-properties here
					  (- (point) (length forms--dyntext)))))))
	  (` ((let ((forms--dyntext (aref forms--dyntexts (, forms--dyntext))))
		(if (not (looking-at (regexp-quote forms--dyntext)))
		    (error "Parse error: not looking at \"%s\"" forms--dyntext))
		(forward-char (length forms--dyntext))))))
      (setq forms--dyntext (1+ forms--dyntext))
      (setq forms--seen-text t)
      (setq forms--field nil)))
   ))

(defun forms--intuit-from-file ()
  "Get number of fields and a default form using the data file."

  ;; If `forms-number-of-fields' is not set, get it from the data file.
  (if (null forms-number-of-fields)

      ;; Need a file to do this.
      (if (not (file-exists-p forms-file))
	  (error "Need existing file or explicit 'forms-number-of-records'.")

	;; Visit the file and extract the first record.
	(setq forms--file-buffer (find-file-noselect forms-file))
	(let ((read-file-filter forms-read-file-filter)
	      (the-record))
	  (setq the-record
		(save-excursion
		  (set-buffer forms--file-buffer)
		  (let ((inhibit-read-only t))
		    (run-hooks 'read-file-filter))
		  (goto-char (point-min))
		  (forms--get-record)))

	  ;; This may be overkill, but try to avoid interference with 
	  ;; the normal processing.
	  (kill-buffer forms--file-buffer)

	  ;; Count the number of fields in `the-record'.
	  (let (the-result
		(start-pos 0)
		found-pos
		(field-sep-length (length forms-field-sep)))
	    (setq forms-number-of-fields 1)
	    (while (setq found-pos
			 (string-match forms-field-sep the-record start-pos))
	      (progn
		(setq forms-number-of-fields (1+ forms-number-of-fields))
		(setq start-pos (+ field-sep-length found-pos))))))))

  ;; Construct default format list.
  (setq forms-format-list (list "Forms file \"" forms-file "\".\n\n"))
  (let ((i 0))
    (while (<= (setq i (1+ i)) forms-number-of-fields)
      (setq forms-format-list
	    (append forms-format-list
		    (list (format "%4d: " i) i "\n"))))))

(defun forms--set-keymaps ()
  "Set the keymaps used in this mode."

  (use-local-map (if forms-read-only 
		     forms-mode-ro-map 
		   forms-mode-edit-map)))

(defun forms--mode-commands ()
  "Fill the Forms mode keymaps."

  ;; `forms-mode-map' is always accessible via \C-c prefix.
  (setq forms-mode-map (make-keymap))
  (define-key forms-mode-map "\t" 'forms-next-field)
  (define-key forms-mode-map "\C-k" 'forms-delete-record)
  (define-key forms-mode-map "\C-q" 'forms-toggle-read-only)
  (define-key forms-mode-map "\C-o" 'forms-insert-record)
  (define-key forms-mode-map "\C-l" 'forms-jump-record)
  (define-key forms-mode-map "\C-n" 'forms-next-record)
  (define-key forms-mode-map "\C-p" 'forms-prev-record)
  (define-key forms-mode-map "\C-r" 'forms-search-backward)
  (define-key forms-mode-map "\C-s" 'forms-search-forward)
  (define-key forms-mode-map "\C-x" 'forms-exit)
  (define-key forms-mode-map "<" 'forms-first-record)
  (define-key forms-mode-map ">" 'forms-last-record)
  (define-key forms-mode-map "\C-?" 'forms-prev-record)

  ;; `forms-mode-ro-map' replaces the local map when in read-only mode.
  (setq forms-mode-ro-map (make-keymap))
  (suppress-keymap forms-mode-ro-map)
  (define-key forms-mode-ro-map "\C-c" forms-mode-map)
  (define-key forms-mode-ro-map "\t" 'forms-next-field)
  (define-key forms-mode-ro-map "q" 'forms-toggle-read-only)
  (define-key forms-mode-ro-map "l" 'forms-jump-record)
  (define-key forms-mode-ro-map "n" 'forms-next-record)
  (define-key forms-mode-ro-map "p" 'forms-prev-record)
  (define-key forms-mode-ro-map "r" 'forms-search-backward)
  (define-key forms-mode-ro-map "s" 'forms-search-forward)
  (define-key forms-mode-ro-map "x" 'forms-exit)
  (define-key forms-mode-ro-map "<" 'forms-first-record)
  (define-key forms-mode-ro-map ">" 'forms-last-record)
  (define-key forms-mode-ro-map "?" 'describe-mode)
  (define-key forms-mode-ro-map " " 'forms-next-record)
  (forms--mode-commands1 forms-mode-ro-map)
  (forms--mode-menu-ro forms-mode-ro-map)

  ;; This is the normal, local map.
  (setq forms-mode-edit-map (make-keymap))
  (define-key forms-mode-edit-map "\t"   'forms-next-field)
  (define-key forms-mode-edit-map "\C-c" forms-mode-map)
  (forms--mode-commands1 forms-mode-edit-map)
  (forms--mode-menu-edit forms-mode-edit-map)
  )

(defun forms--mode-menu-ro (map)
;;; Menu initialisation
;  (define-key map [menu-bar] (make-sparse-keymap))
  (define-key map [menu-bar forms]
    (cons "Forms" (make-sparse-keymap "Forms")))
  (define-key map [menu-bar forms menu-forms-exit]
    '("Exit Forms Mode" . forms-exit))
  (define-key map [menu-bar forms menu-forms-sep1]
    '("----"))
  (define-key map [menu-bar forms menu-forms-save]
    '("Save Data" . forms-save-buffer))
  (define-key map [menu-bar forms menu-forms-print]
    '("Print Data" . forms-print))
  (define-key map [menu-bar forms menu-forms-describe]
    '("Describe Mode" . describe-mode))
  (define-key map [menu-bar forms menu-forms-toggle-ro]
    '("Toggle View/Edit" . forms-toggle-read-only))
  (define-key map [menu-bar forms menu-forms-jump-record]
    '("Jump" . forms-jump-record))
  (define-key map [menu-bar forms menu-forms-search-backward]
    '("Search Backward" . forms-search-backward))
  (define-key map [menu-bar forms menu-forms-search-forward]
    '("Search Forward" . forms-search-forward))
  (define-key map [menu-bar forms menu-forms-delete-record]
    '("Delete" . forms-delete-record))
  (define-key map [menu-bar forms menu-forms-insert-record]
    '("Insert" . forms-insert-record))
  (define-key map [menu-bar forms menu-forms-sep2]
    '("----"))
  (define-key map [menu-bar forms menu-forms-last-record]
    '("Last Record" . forms-last-record))
  (define-key map [menu-bar forms menu-forms-first-record]
    '("First Record" . forms-first-record))
  (define-key map [menu-bar forms menu-forms-prev-record]
    '("Previous Record" . forms-prev-record))
  (define-key map [menu-bar forms menu-forms-next-record]
    '("Next Record" . forms-next-record))
  (define-key map [menu-bar forms menu-forms-sep3]
    '("----"))
  (define-key map [menu-bar forms menu-forms-prev-field]
    '("Previous Field" . forms-prev-field))
  (define-key map [menu-bar forms menu-forms-next-field]
    '("Next Field" . forms-next-field))
  (put 'forms-insert-record 'menu-enable '(not forms-read-only))
  (put 'forms-delete-record 'menu-enable '(not forms-read-only))
)
(defun forms--mode-menu-edit (map)
;;; Menu initialisation
;  (define-key map [menu-bar] (make-sparse-keymap))
  (define-key map [menu-bar forms]
    (cons "Forms" (make-sparse-keymap "Forms")))
  (define-key map [menu-bar forms menu-forms-edit--exit]
    '("Exit" . forms-exit))
  (define-key map [menu-bar forms menu-forms-edit-sep1]
    '("----"))
  (define-key map [menu-bar forms menu-forms-edit-save]
    '("Save Data" . forms-save-buffer))
  (define-key map [menu-bar forms menu-forms-edit-print]
    '("Print Data" . forms-print))
  (define-key map [menu-bar forms menu-forms-edit-describe]
    '("Describe Mode" . describe-mode))
  (define-key map [menu-bar forms menu-forms-edit-toggle-ro]
    '("Toggle View/Edit" . forms-toggle-read-only))
  (define-key map [menu-bar forms menu-forms-edit-jump-record]
    '("Jump" . forms-jump-record))
  (define-key map [menu-bar forms menu-forms-edit-search-backward]
    '("Search Backward" . forms-search-backward))
  (define-key map [menu-bar forms menu-forms-edit-search-forward]
    '("Search Forward" . forms-search-forward))
  (define-key map [menu-bar forms menu-forms-edit-delete-record]
    '("Delete" . forms-delete-record))
  (define-key map [menu-bar forms menu-forms-edit-insert-record]
    '("Insert" . forms-insert-record))
  (define-key map [menu-bar forms menu-forms-edit-sep2]
    '("----"))
  (define-key map [menu-bar forms menu-forms-edit-last-record]
    '("Last Record" . forms-last-record))
  (define-key map [menu-bar forms menu-forms-edit-first-record]
    '("First Record" . forms-first-record))
  (define-key map [menu-bar forms menu-forms-edit-prev-record]
    '("Previous Record" . forms-prev-record))
  (define-key map [menu-bar forms menu-forms-edit-next-record]
    '("Next Record" . forms-next-record))
  (define-key map [menu-bar forms menu-forms-edit-sep3]
    '("----"))
  (define-key map [menu-bar forms menu-forms-edit-prev-field]
    '("Previous Field" . forms-prev-field))
  (define-key map [menu-bar forms menu-forms-edit-next-field]
    '("Next Field" . forms-next-field))
  (put 'forms-insert-record 'menu-enable '(not forms-read-only))
  (put 'forms-delete-record 'menu-enable '(not forms-read-only))
)

(defun forms--mode-commands1 (map) 
  "Helper routine to define keys."
  (define-key map [TAB] 'forms-next-field)
  (define-key map [S-tab] 'forms-prev-field)
  (define-key map [next] 'forms-next-record)
  (define-key map [prior] 'forms-prev-record)
  (define-key map [begin] 'forms-first-record)
  (define-key map [last] 'forms-last-record)
  (define-key map [backtab] 'forms-prev-field)
  )

;;; Changed functions

(defun forms--change-commands ()
  "Localize some commands for Forms mode."

  ;; scroll-down -> forms-prev-record
  ;; scroll-up -> forms-next-record
  (if forms-forms-scroll
      (progn
	(substitute-key-definition 'scroll-up 'forms-next-record
				   (current-local-map)
				   (current-global-map))
	(substitute-key-definition 'scroll-down 'forms-prev-record
				   (current-local-map)
				   (current-global-map))))
  ;;
  ;; beginning-of-buffer -> forms-first-record
  ;; end-of-buffer -> forms-end-record
  (if forms-forms-jump
      (progn
	(substitute-key-definition 'beginning-of-buffer 'forms-first-record
				   (current-local-map)
				   (current-global-map))
	(substitute-key-definition 'end-of-buffer 'forms-last-record
				   (current-local-map)
				   (current-global-map))))
  ;;
  ;; Save buffer
  (local-set-key "\C-x\C-s" 'forms-save-buffer)
  ;;
  ;; We have our own revert function - use it.
  (make-local-variable 'revert-buffer-function)
  (setq revert-buffer-function 'forms--revert-buffer)

  t)

(defun forms--help ()
  "Initial help for Forms mode."
  (message "%s" (substitute-command-keys (concat
  "\\[forms-next-record]:next"
  "   \\[forms-prev-record]:prev"
  "   \\[forms-first-record]:first"
  "   \\[forms-last-record]:last"
  "   \\[describe-mode]:help"))))

(defun forms--trans (subj arg rep)
  "Translate in SUBJ all chars ARG into char REP.  ARG and REP should
 be single-char strings."
  (let ((i 0)
	(x (length subj))
	(re (regexp-quote arg))
	(k (string-to-char rep)))
    (while (setq i (string-match re subj i))
      (aset subj i k)
      (setq i (1+ i)))))

(defun forms--exit (query &optional save)
  "Internal exit from forms mode function."

  (let ((buf (buffer-name forms--file-buffer)))
    (forms--checkmod)
    (if (and save
	     (buffer-modified-p forms--file-buffer))
	(forms-save-buffer))
    (save-excursion
      (set-buffer forms--file-buffer)
      (delete-auto-save-file-if-necessary)
      (kill-buffer (current-buffer)))
    (if (get-buffer buf)	; not killed???
      (if save
	  (progn
	    (beep)
	    (message "Problem saving buffers?")))
      (delete-auto-save-file-if-necessary)
      (kill-buffer (current-buffer)))))

(defun forms--get-record ()
  "Fetch the current record from the file buffer."

  ;; This function is executed in the context of the `forms--file-buffer'.

  (or (bolp)
      (beginning-of-line nil))
  (let ((here (point)))
    (prog2
     (end-of-line)
     (buffer-substring-no-properties here (point))
     (goto-char here))))

(defun forms--show-record (the-record)
  "Format THE-RECORD and display it in the current buffer."

  ;; Split the-record.
  (let (the-result
	(start-pos 0)
	found-pos
	(field-sep-length (length forms-field-sep)))
    (if forms-multi-line
	(forms--trans the-record forms-multi-line "\n"))
    ;; Add an extra separator (makes splitting easy).
    (setq the-record (concat the-record forms-field-sep))
    (while (setq found-pos (string-match forms-field-sep the-record start-pos))
      (let ((ent (substring the-record start-pos found-pos)))
	(setq the-result
	      (append the-result (list ent)))
	(setq start-pos (+ field-sep-length found-pos))))
    (setq forms--the-record-list the-result))

  (setq buffer-read-only nil)
  (if forms-use-text-properties
      (let ((inhibit-read-only t))
	(set-text-properties (point-min) (point-max) nil)))
  (erase-buffer)

  ;; Verify the number of fields, extend forms--the-record-list if needed.
  (if (= (length forms--the-record-list) forms-number-of-fields)
      nil
    (if (null forms-check-number-of-fields)
	nil
      (beep)
      (message "Warning: this record has %d fields instead of %d"
	       (length forms--the-record-list) forms-number-of-fields))
    (if (< (length forms--the-record-list) forms-number-of-fields)
	(setq forms--the-record-list 
	      (append forms--the-record-list
		      (make-list 
		       (- forms-number-of-fields 
			  (length forms--the-record-list))
		       "")))))

  ;; Call the formatter function.
  (setq forms-fields (append (list nil) forms--the-record-list nil))
  (funcall forms--format forms--the-record-list)

  ;; Prepare.
  (goto-char (point-min))
  (set-buffer-modified-p nil)
  (setq buffer-read-only forms-read-only)
  (setq mode-line-process
	(concat " " forms--current-record "/" forms--total-records)))

(defun forms--parse-form ()
  "Parse contents of form into list of strings."
  ;; The contents of the form are parsed, and a new list of strings
  ;; is constructed.
  ;; A vector with the strings from the original record is 
  ;; constructed, which is updated with the new contents.  Therefore
  ;; fields which were not in the form are not modified.
  ;; Finally, the vector is transformed into a list for further processing.

  (let (forms--recordv)

    ;; Build the vector.
    (setq forms--recordv (vconcat forms--the-record-list))

    ;; Parse the form and update the vector.
    (let ((forms--dynamic-text forms--dynamic-text))
      (funcall forms--parser))

    (if forms-modified-record-filter
	;; As a service to the user, we add a zeroth element so she
	;; can use the same indices as in the forms definition.
	(let ((the-fields (vconcat [nil] forms--recordv)))
	  (setq the-fields (funcall forms-modified-record-filter the-fields))
	  (cdr (append the-fields nil)))

      ;; Transform to a list and return.
      (append forms--recordv nil))))

(defun forms--update ()
  "Update current record with contents of form.
As a side effect: sets `forms--the-record-list'."

  (if forms-read-only
      (progn
	(message "Read-only buffer!")
	(beep))

    (let (the-record)
      ;; Build new record.
      (setq forms--the-record-list (forms--parse-form))
      (setq the-record
	    (mapconcat 'identity forms--the-record-list forms-field-sep))

      (if (string-match (regexp-quote forms-field-sep)
			(mapconcat 'identity forms--the-record-list ""))
	  (error "Field separator occurs in record - update refused!"))

      ;; Handle multi-line fields, if allowed.
      (if forms-multi-line
	  (forms--trans the-record "\n" forms-multi-line))

      ;; A final sanity check before updating.
      (if (string-match "\n" the-record)
	  (progn
	    (message "Multi-line fields in this record - update refused!")
	    (beep))

	(save-excursion
	  (set-buffer forms--file-buffer)
	  ;; Use delete-region instead of kill-region, to avoid
	  ;; adding junk to the kill-ring.
	  (delete-region (save-excursion (beginning-of-line) (point))
			 (save-excursion (end-of-line) (point)))
	  (insert the-record)
	  (beginning-of-line))))))

(defun forms--checkmod ()
  "Check if this form has been modified, and call forms--update if so."
  (if (buffer-modified-p nil)
      (let ((here (point)))
	(forms--update)
	(set-buffer-modified-p nil)
	(goto-char here))))

;;; Start and exit

;;;###autoload
(defun forms-find-file (fn)
  "Visit a file in Forms mode."
  (interactive "fForms file: ")
  (let ((enable-local-eval t)
	(enable-local-variables t))
    (find-file-read-only fn)
    (or forms--mode-setup (forms-mode t))))

;;;###autoload
(defun forms-find-file-other-window (fn)
  "Visit a file in Forms mode in other window."
  (interactive "fFbrowse file in other window: ")
  (let ((enable-local-eval t)
	(enable-local-variables t))
    (find-file-other-window fn)
    (or forms--mode-setup (forms-mode t))))

(defun forms-exit (query)
  "Normal exit from Forms mode.  Modified buffers are saved."
  (interactive "P")
  (forms--exit query t))

(defun forms-exit-no-save (query)
  "Exit from Forms mode without saving buffers."
  (interactive "P")
  (forms--exit query nil))

;;; Navigating commands

(defun forms-next-record (arg)
  "Advance to the ARGth following record."
  (interactive "P")
  (forms-jump-record (+ forms--current-record (prefix-numeric-value arg)) t))

(defun forms-prev-record (arg)
  "Advance to the ARGth previous record."
  (interactive "P")
  (forms-jump-record (- forms--current-record (prefix-numeric-value arg)) t))

(defun forms-jump-record (arg &optional relative)
  "Jump to a random record."
  (interactive "NRecord number: ")

  ;; Verify that the record number is within range.
  (if (or (> arg forms--total-records)
	  (<= arg 0))
    (progn
      (beep)
      ;; Don't give the message if just paging.
      (if (not relative)
	  (message "Record number %d out of range 1..%d"
		   arg forms--total-records))
      )

    ;; Flush.
    (forms--checkmod)

    ;; Calculate displacement.
    (let ((disp (- arg forms--current-record))
	  (cur forms--current-record))

      ;; `forms--show-record' needs it now.
      (setq forms--current-record arg)

      ;; Get the record and show it.
      (forms--show-record
       (save-excursion
	 (set-buffer forms--file-buffer)
	 (beginning-of-line)

	 ;; Move, and adjust the amount if needed (shouldn't happen).
	 (if relative
	     (if (zerop disp)
		 nil
	       (setq cur (+ cur disp (- (forward-line disp)))))
	   (setq cur (+ cur disp (- (goto-line arg)))))

	 (forms--get-record)))

      ;; This shouldn't happen.
      (if (/= forms--current-record cur)
	  (progn
	    (setq forms--current-record cur)
	    (beep)
	    (message "Stuck at record %d" cur))))))

(defun forms-first-record ()
  "Jump to first record."
  (interactive)
  (forms-jump-record 1))

(defun forms-last-record ()
  "Jump to last record.
As a side effect: re-calculates the number of records in the data file."
  (interactive)
  (let
      ((numrec 
	(save-excursion
	  (set-buffer forms--file-buffer)
	  (count-lines (point-min) (point-max)))))
    (if (= numrec forms--total-records)
	nil
      (beep)
      (setq forms--total-records numrec)
      (message "Warning: number of records changed to %d" forms--total-records)))
  (forms-jump-record forms--total-records))

;;; Other commands

(defun forms-toggle-read-only (arg)
  "Toggles read-only mode of a forms mode buffer.
With an argument, enables read-only mode if the argument is positive.
Otherwise enables edit mode if the visited file is writable."

  (interactive "P")

  (if (if arg
	  ;; Negative arg means switch it off.
	  (<= (prefix-numeric-value arg) 0)
	;; No arg means toggle.
	forms-read-only)

      ;; Enable edit mode, if possible.
      (let ((ro forms-read-only))
	(if (save-excursion
	      (set-buffer forms--file-buffer)
	      buffer-read-only)
	    (progn
	      (setq forms-read-only t)
	      (message "No write access to `%s'" forms-file)
	      (beep))
	  (setq forms-read-only nil))
	(if (equal ro forms-read-only)
	    nil
	  (forms-mode)))

    ;; Enable view mode.
    (if forms-read-only
	nil
      (forms--checkmod)			; sync
      (setq forms-read-only t)
      (forms-mode))))

;; Sample:
;; (defun my-new-record-filter (the-fields)
;;   ;; numbers are relative to 1
;;   (aset the-fields 4 (current-time-string))
;;   (aset the-fields 6 (user-login-name))
;;   the-list)
;; (setq forms-new-record-filter 'my-new-record-filter)

(defun forms-insert-record (arg)
  "Create a new record before the current one.
With ARG: store the record after the current one.
If `forms-new-record-filter' contains the name of a function, 
it is called to fill (some of) the fields with default values.
If `forms-insert-after is non-nil, the default behavior is to insert
after the current record."

  (interactive "P")

  (if forms-read-only
      (error ""))

  (let (ln the-list the-record)

    (if (or (and arg forms-insert-after)
	    (and (not arg) (not forms-insert-after)))
	(setq ln forms--current-record)
      (setq ln (1+ forms--current-record)))

    (forms--checkmod)
    (if forms-new-record-filter
	;; As a service to the user, we add a zeroth element so she
	;; can use the same indices as in the forms definition.
	(let ((the-fields (make-vector (1+ forms-number-of-fields) "")))
	  (setq the-fields (funcall forms-new-record-filter the-fields))
	  (setq the-list (cdr (append the-fields nil))))
      (setq the-list (make-list forms-number-of-fields "")))

    (setq the-record
	  (mapconcat
	  'identity
	  the-list
	  forms-field-sep))

    (save-excursion
      (set-buffer forms--file-buffer)
      (goto-line ln)
      (open-line 1)
      (insert the-record)
      (beginning-of-line))
    
    (setq forms--current-record ln))

  (setq forms--total-records (1+ forms--total-records))
  (forms-jump-record forms--current-record))

(defun forms-delete-record (arg)
  "Deletes a record.  With a prefix argument: don't ask."
  (interactive "P")

  (if forms-read-only
      (error ""))

  (forms--checkmod)
  (if (or arg
	  (y-or-n-p "Really delete this record? "))
      (let ((ln forms--current-record))
	(save-excursion
	  (set-buffer forms--file-buffer)
	  (goto-line ln)
	  ;; Use delete-region instead of kill-region, to avoid
	  ;; adding junk to the kill-ring.
	  (delete-region (progn (beginning-of-line) (point))
			 (progn (beginning-of-line 2) (point))))
	(setq forms--total-records (1- forms--total-records))
	(if (> forms--current-record forms--total-records)
	    (setq forms--current-record forms--total-records))
	(forms-jump-record forms--current-record)))
  (message ""))

(defun forms-search-forward (regexp)
  "Search forward for record containing REGEXP."
  (interactive 
   (list (read-string (concat "Search forward for" 
				  (if forms--search-regexp
				   (concat " ("
					   forms--search-regexp
					   ")"))
				  ": "))))
  (if (equal "" regexp)
      (setq regexp forms--search-regexp))
  (forms--checkmod)

  (let (the-line the-record here
		 (fld-sep forms-field-sep))
    (if (save-excursion
	  (set-buffer forms--file-buffer)
	  (setq here (point))
	  (end-of-line)
	  (if (null (re-search-forward regexp nil t))
	      (progn
		(goto-char here)
		(message "\"%s\" not found" regexp)
		nil)
	    (setq the-record (forms--get-record))
	    (setq the-line (1+ (count-lines (point-min) (point))))))
	(progn
	  (setq forms--current-record the-line)
	  (forms--show-record the-record)
	  (re-search-forward regexp nil t))))
  (setq forms--search-regexp regexp))

(defun forms-search-backward (regexp)
  "Search backward for record containing REGEXP."
  (interactive 
   (list (read-string (concat "Search backward for" 
				  (if forms--search-regexp
				   (concat " ("
					   forms--search-regexp
					   ")"))
				  ": "))))
  (if (equal "" regexp)
      (setq regexp forms--search-regexp))
  (forms--checkmod)

  (let (the-line the-record here
		 (fld-sep forms-field-sep))
    (if (save-excursion
	  (set-buffer forms--file-buffer)
	  (setq here (point))
	  (beginning-of-line)
	  (if (null (re-search-backward regexp nil t))
	      (progn
		(goto-char here)
		(message "\"%s\" not found" regexp)
		nil)
	    (setq the-record (forms--get-record))
	    (setq the-line (1+ (count-lines (point-min) (point))))))
	(progn
	  (setq forms--current-record the-line)
	  (forms--show-record the-record)
	  (re-search-forward regexp nil t))))
  (setq forms--search-regexp regexp))

(defun forms-save-buffer (&optional args)
  "Forms mode replacement for save-buffer.
It saves the data buffer instead of the forms buffer.
Calls `forms-write-file-filter' before writing out the data."
  (interactive "p")
  (forms--checkmod)
  (let ((read-file-filter forms-read-file-filter))
    (save-excursion
      (set-buffer forms--file-buffer)
      (let ((inhibit-read-only t))
	(save-buffer args)
	(if read-file-filter
	    (run-hooks 'read-file-filter))
	(set-buffer-modified-p nil))))
  t)

(defun forms--revert-buffer (&optional arg noconfirm)
  "Reverts current form to un-modified."
  (interactive "P")
  (if (or noconfirm
	  (yes-or-no-p "Revert form to unmodified? "))
      (progn
	(set-buffer-modified-p nil)
	(forms-jump-record forms--current-record))))

(defun forms-next-field (arg)
  "Jump to ARG-th next field."
  (interactive "p")

  (let ((i 0)
	(here (point))
	there
	(cnt 0)
	(inhibit-point-motion-hooks t))

    (if (zerop arg)
	(setq cnt 1)
      (setq cnt (+ cnt arg)))

    (if (catch 'done
	  (while (< i (length forms--markers))
	    (if (or (null (setq there (aref forms--markers i)))
		    (<= there here))
		nil
	      (if (<= (setq cnt (1- cnt)) 0)
		  (progn
		    (goto-char there)
		    (throw 'done t))))
	    (setq i (1+ i))))
	nil
      (goto-char (aref forms--markers 0)))))

(defun forms-prev-field (arg)
  "Jump to ARG-th previous field."
  (interactive "p")

  (let ((i (length forms--markers))
	(here (point))
	there
	(cnt 0)
	(inhibit-point-motion-hooks t))

    (if (zerop arg)
	(setq cnt 1)
      (setq cnt (+ cnt arg)))

    (if (catch 'done
	  (while (> i 0)
	    (setq i ( 1- i))
	    (if (or (null (setq there (aref forms--markers i)))
		    (>= there here))
		nil
	      (if (<= (setq cnt (1- cnt)) 0)
		  (progn
		    (goto-char there)
		    (throw 'done t))))))
	nil
      (goto-char (aref forms--markers (1- (length forms--markers)))))))

(defun forms-print ()
  "Send the records to the printer with 'print-buffer', one record per page."
  (interactive)
  (let ((inhibit-read-only t)
	(save-record forms--current-record)
	(nb-record 1)
	(record nil))
    (while (<= nb-record forms--total-records)
      (forms-jump-record nb-record)
      (setq record (buffer-string))
      (save-excursion
	(set-buffer (get-buffer-create "*forms-print*"))
	(goto-char (buffer-end 1))
	(insert record)
	(setq buffer-read-only nil)
	(if (< nb-record forms--total-records)
	    (insert "\n\n")))
      (setq nb-record (1+ nb-record)))
    (save-excursion
      (set-buffer "*forms-print*")
      (print-buffer)
      (set-buffer-modified-p nil)
      (kill-buffer (current-buffer)))
    (forms-jump-record save-record)))

;;;
;;; Special service
;;;
(defun forms-enumerate (the-fields)
  "Take a quoted list of symbols, and set their values to sequential numbers.
The first symbol gets number 1, the second 2 and so on.
It returns the highest number.

Usage: (setq forms-number-of-fields
             (forms-enumerate
              '(field1 field2 field2 ...)))"

  (let ((the-index 0))
    (while the-fields
      (setq the-index (1+ the-index))
      (let ((el (car-safe the-fields)))
	(setq the-fields (cdr-safe the-fields))
	(set el the-index)))
    the-index))

;;; Debugging

(defvar forms--debug nil
  "*Enables forms-mode debugging if not nil.")

(defun forms--debug (&rest args)
  "Internal debugging routine."
  (if forms--debug
      (let ((ret nil))
	(while args
	  (let ((el (car-safe args)))
	    (setq args (cdr-safe args))
	    (if (stringp el)
		(setq ret (concat ret el))
	      (setq ret (concat ret (prin1-to-string el) " = "))
	      (if (boundp el)
		  (let ((vel (eval el)))
		    (setq ret (concat ret (prin1-to-string vel) "\n")))
		(setq ret (concat ret "<unbound>" "\n")))
	      (if (fboundp el)
		  (setq ret (concat ret (prin1-to-string (symbol-function el)) 
				    "\n"))))))
	(save-excursion
	  (set-buffer (get-buffer-create "*forms-mode debug*"))
	  (if (zerop (buffer-size))
	      (emacs-lisp-mode))
	  (goto-char (point-max))
	  (insert ret)))))

;;; forms.el ends here.
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.